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Understanding the behavior of SiO2 under different external conditions, particularly pressure, is essential for advancing its applications. While existing literature primarily focuses on the impact of isotropic stress on SiO2, there remains a gap in exploring the effects of uniaxial and biaxial stresses on its properties. This study aims to address this gap by investigating the novel effects of uniaxial, biaxial, and isotropic pressures on the opto-electrical properties of SiO2 using first principles calculations. Our results reveal distinct structural adaptations of SiO2 under different pressure conditions, demonstrating its anisotropic behavior. For example, under isotropic pressure in the interval [0.0, 12.5] GPa, the lattice parameters 5.039 < a < 4.615 Å, and 5.529 < c < 5.239 Å, and the unit cell volume ranged from 121.57 to 96.65 Å3 show reductions in values, indicating structural compression in accordance with the experimentally found values. Additionally, we investigated the electrical properties, including the complex dielectric function and conductivity. At an isotropic pressure of 0 GPa, the real refractive index of SiO2 is approximately n = 2.04083, which increases to n = 2.20836 at 12.5 GPa, while applying uniaxial or biaxial pressure resulted in direction-dependent-refractive index highlighting the crystal's anisotropic to external pressure. Also, our study revealed that the maximum values of conductivity increased while wavelength shift decreased as a function of the applied stress on the crystal. These findings provide valuable insights into the behavior of SiO2 single crystal under directional stresses, facilitating the design of pressure-sensitive optoelectronic devices. [ABSTRACT FROM AUTHOR]

Effects on mechanical and γ-ray shielding competence of TiO2-based glasses of chemical composition: 30PbO⋅4MoO3⋅(66 − z)B2O3⋅zTiO2 (0.0 < z < 2.0 mol%) was calculated in this report. The glass density was found to increase in the range of 4.650–4.696 g/cm3 concurrent with a decline in the oxygen molar volume (OMV) from 10.633 to10.547 cm3/mol when [Ti4+] molar fraction is increased in the glass samples. The Gibbs free energy was found to be between 20.874 and 22.586 kJ/cm3 and was found to be influenced by TiO2 concentration in these glasses and on the valance states of Ti3+ and Mo5+. The affinity of mass attenuation coefficient (MAC) values (0.039 < MAC < 6.198 g/cm3) in the examined photon energy domain 0.015 < E < 15.0 MeV has the following chronological sorting: MACT0 < MACT2 < MACT4 < MACT6 < MACT8 < MACT10 < MACT15 < MACT20. The half-value-layer (HVL) trend of Mo-glasses was balanced against two standard RS-glass systems and discovered to possess a less γ-ray shielding competence as RS-(360, 520) or concrete. Also, we found that when the [Ti3+]/[Mo5+] ratio exceeds 0.8 mol%, then both ions participate in the studied properties via de-polymerization of the glass network. These outcomes revealed that the safety effectiveness against radiation and physic-mechano-properties can be synchronized for diverse purposes. [ABSTRACT FROM AUTHOR]

OBJECTIVE: One of the major concerns of the post-COVID-19 era is elucidating and addressing the long-term complications of COVID-19. SUBJECTS AND METHODS: A web-based questionnaire was distributed in Jordan to assess the prevalence and recovery from chemosensory dysfunction among COVID-19 long-haulers in Jordan. RESULTS: A total of 611 respondents complained of chemosensory dysfunction (age range = 18-68 years), and the majority of the respondents were female (88.4%). Parosmia was the most prevalent olfactory dysfunction reported (n = 337, 33.3%), and parageusia was the most frequently reported gustatory dysfunction (n = 239, 36.4%). Medications were not reported to be associated with a better perception of smell or taste by nearly half of those who had been treated (n = 146, 46.1%). Among participants who had received olfactory rehabilitation/ training (n = 215, 35.2%), 43.7% (n = 94) reported modest improvement, with the most frequently helpful scents being coffee (n = 80, 24.8%), aromatic oils (n = 74, 23%), and perfumes/colognes (n = 73, 22.7%). Age was found to have a significant negative correlation with complete recovery. In addition, age (p < .05), anosmia (p < .001), hyperosmia (p < .001), ageusia (p < .05), and duration of olfactory dysfunction (p < .001) were all independent predictors of complete recovery. CONCLUSIONS: Chemosensory dysfunctions are largely subjective; therefore, more objective examinations are required to draw more definite conclusions. [ABSTRACT FROM AUTHOR]

The radiation, elastic-mechanic-characteristics of LMAS (Li2O-MgO-Al2O3-SiO2) glass systems influenced by the molar ratio [SiO2]/([P2O5] + [Al2O3]) additions were investigated. Within the incoming photon energies: 0.015 to 15.0 MeV spanned in this study, both XCOM and Phy-X/PSD codes were utilized. The outcomes demonstrate that substituting P2O5 with Al2O3 at the expense of SiO2 led to an increase in glass density from 3.021 to 3.26 g/cm3, which, in turn, decreased the LAC from 2.633 to 2.534 cm−1 at E = 400 keV. The MAC values were found to be 6.721 < MAC < 7.004 g/cm2 at low photon energy.The uppermost values of MAC were observed for the glass-system encoded as 0P-5AF with a direct relationship to energy. The highest effective-atomic-number (Zeff) was recorded at E = 20 keV, and ranged from 18.13 to 19.31 for the LMAS samples. Subsequently, Zeff declined rapidly to a value around 9.75 at E = 1.0 MeV, and slightly increased above E = 1.50 MeV. Furthermore, the tenth-value-layer (TVL) values bare that an decrease of [SiO2]/([P2O5] + [Al2O3]) mol% from 0.0 to 20.8% decreased the thickness required to stop or obstruct photons (e.g., 11.974 < TVL < 11.241 cm at E = 1.0 MeV). The 3P-5A sample exhibited the highest half-value-layer 0.033 < HVL < 10.666 cm, while the 2P-16A sample had the lowest HVL. The optimized ratio [SiO2]/([P2O5] + [Al2O3]) was found to be 6.8.The radiation shield hallmarks of the LMAS glass blocks developed as the ratio [SiO2]/([P2O5] + [Al2O3]) enhanced in the glass samples. The elastic moduli were found to depend on this ratio content molar concentration. Accordingly, the radiation shielding properties are also correlated in same manner. Also, the calculated elastic-mechanical intrinsic of these transparent blocks, include the molar volume (Vm), which increased from 18.157 to 19.92 cm3/mol, and the free-energy (G) from 71.895 to 83.313 kJ/cm3 were found to depend on the nominated mol%. [ABSTRACT FROM AUTHOR]

The role of the [Na2O]/[CuO] ratio in two glass groups with a chemical formula of (50 − y/2)Na2O–yCuO–(50 − y/2) P2O5 (y = 0.0–40 mol%) coded as Line I and (50 − y)Na2O–yCuO–50P2O5 (y = 0.0–50 mol%) coded as Line II on physical and gamma-ray attenuation properties have been deeply investigated. The density (ρ) varied from 2.471 to 3.262 g/cm3 and from 2.471 to 3.113 g/cm3 for Line I and Line II glasses, respectively. The molar volume (Vm) values varied from 41.280 to 28.526 cm3/mol and from 41.280 to 35.609 cm3/mol for Line I and Line II glasses, respectively. The oxygen molar volume (OMV) reduced from 13.761 to12.972 cm3/mol and from 13.761 to 11.873 cm3/mol, while the oxygen packing density (OPD) improved from 72.674 to 77.124 and from 72.674 to 84.253 g.atom/l for Line I and Line II glasses. The mass and linear attenuation coefficients (MAC and LAC) values corresponding to the Line II glass is slightly lower than their counterpart of the Line I. The effective atomic numbers (Zeff) and electron density (Neff) for glasses in Line I was lower than that for those in Line II. Exposure (EBF) and energy absorption (EABF) buildup factors have the same trend in both glass groups. The findings support the capability to utilize the examined glasses as radiation shielding materials. [ABSTRACT FROM AUTHOR]

The desired target of the current report was to examine the efficiency of MnO-based glass systems against x- or g-rays, and mechanical properties with varying amounts of MnO incorporation. The focus was on evaluating their radiation shielding performance and determining their elasto-mechanic intrinsic characteristics. Various gamma and neutron shielding factors, including HVL (half-value layer), Zeff (Zeff: effective atomic number), Zeq (equivalent atomic number), EBF (exposure buildup factor), EABF (energy absorption buildup factor), ACS (atomic cross-section), ESC (electronic cross-section), and SAFE* (specific absorbed fraction of energy) were planned to assess the radio-protection capabilities of the probed glass systems. Exemplified at E = 15 keV, the MAC (mass attenuation coefficient) values are: 13.99 cm2/g, 14.03 cm2/g, 14.18 cm2/g, 14.36 cm2/g, and 14.55 cm2/g for the glass blocks encoded as LZBP, 0.1Mn:LZBP, 0.5Mn:LZBP, 1.0Mn:LZBP, and 1.5Mn:LZBP respectively, while the SAFE values vary between 31907 g−1 and 32013 g−1 as Mn2+ is increased from 0.0 mol% to 1.5 mol%. The outcomes indicate that as the manganese (II) oxide mol% increases, then the MAC, Zeff, Zeq, ACS, and ESC values also increase. Among the samples, 1.5Mn:LZBP exhibited the least HVL, EBF, EABF, and SAFE values. This glass, which contains 1.5 mol% of MnO and has the highest interconnecting bonding/volume, may be deemed as an advanced glass for ray protection in the different fields, providing valuable insights into their radiation shielding performance. [ABSTRACT FROM AUTHOR]

Influence of CuO on the linear/nonlinear optical, elastic, physical features, and radiation protection performance of CuO-based glasses in form (50-y/2)Na2O + (50-y/2)P2O5 + yCuO, (y = 0.0–40 mol%) has been studied in the current article. The density was increased from 2.47 to 3.26 g.cm−3 accomplished with a concurrent decrease in the oxygen molar volume from 13.76 to 12.97 cm3.mol−1 as the mol% of [Cu2+] enhanced in the tested glasses. Also, the Vickers hardness (Hv) was found to increase with increasing CuO content in the current glass systems. The notable tendency of mass attenuation coefficient (MAC) values in the investigated energetic photon range obeyed the sequential order: MACCuI-0 < MACCuI-10 < MACCuI-20 < MACCuI-25 < MACCuI-30 < MACCuI-33 < MACCuI-40. Also, we found that the linear attenuation coefficient (LAC) increased, while the half-value-layer (HVL), and transmission coefficient (TF%) also decreased. The HVL values of the current samples were compared with standard glasses, and it was found to those CuO-based samples possessed a comparable photon protection capacity as RS-360 and RS-520. The linear (nlinear) and nonlinear ( n 2 optical ) refractive index increased from 3.914 to 3.983 and from 2.76 × 10–9 and 3.15 × 10–9. Results uncovered that the optical, radiation protection efficiency and elasto-mechanical characteristics might at the same time be adjusted for an in- or/and out-door scientific and medical applications. [ABSTRACT FROM AUTHOR]

In this article, we aim to develop new k , s -fractional integral and differential operators containing S -functions as kernels in a form of generalized k -Mittag-Leffer functions. We also set up various properties of such operators. Furthermore, we consider a variety of implications of the major outcomes that will be very useful in the implementation of scientific, engineering, and technical problems. [ABSTRACT FROM AUTHOR]

Zinc Telluride (ZnTe) films were prepared by the closed space sublimation (CSS) method. The effect of chemical treatments with concentrated phosphoric acid, on the optical, electric and structural properties of the films was studied. Zinc-blend structure of the polycrystalline nature of the films was confirmed by x-ray diffraction (XRD) spectra. The energy dispersive x-ray (EDX) shows an increase in Te ratio on the surface of the film as exposed to phosphoric acid. In addition, the dc electrical resistivity of the films was dropped considerably. The refractive index, thickness, and thickness irregularity of the films were determined by fitting of the optical transmittance spectra in the wavelength range 400 to 2500 nm. The effect, of treatment, on the optical parameters is also reported. [ABSTRACT FROM AUTHOR]

Older people constitute an overlooked vulnerable population in humanitarian crises. Lebanon is a small country that hosts the largest number of refugees per capita in the world. With exacerbating socioeconomic conditions, exclusionary policies against refugees, and a fragmented humanitarian system, the status of older Syrian refugees (OSRs) requires special attention. This study aimed to explore OSRs' unmet needs, coping strategies, available humanitarian services, and some indicators of the humanitarian inclusion standards focusing on the shelter, health, nutrition and food security, and water, sanitation and hygiene sectors. We conducted a convergent mixed-methods study between December 2021 and March 2022 in the North and Bekaa, including a cross-sectional survey with 461 participants and 14 semi-structured interviews. Results show that OSRs lived in inappropriate shelters (cold, leaking rainwater), especially in informal tented settlements. High rent prices pushed refugee households with elderly to prioritize paying rent at the expense of other needs such as food and medication, particularly when food cash transfer is the sole source of income, jeopardizing food security and intake. Access to dignifying and accessible bathing facilities was compromised in ITSs with shared facilities. Substantial medical costs hindered OSRs access to healthcare such as surgeries. Due to the crisis, chronic medications are not always available in dispensaries for subsidized cost, pushing OSRs to non-compliance and selling food assistance to buy medications. Soaring fuel prices hindered OSRs access to heating and transportation to receive healthcare. No efforts were reported in collecting data on OSRs' needs, targeting them with information on services, or soliciting feedback for programming, especially in the absence of any age-tailored interventions. Findings shed light on the precarious living conditions of OSRs in Lebanon and add to the body of evidence documenting their invisibility to the humanitarian response. An age-inclusive response is needed through holistic, tailored, and sustainable interventions., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Al Omari et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

To assess the clinical practice in the follow-up of non-muscle-invasive bladder cancer (NMIBC) among urology specialists (trainers) and residents (trainees) in Jordan., Methods: An electronic questionnaire containing, in addition to demographic data, four questions regarding the follow-up of NMIBC was sent by e-mail to 115 urologists (53 residents and 62 specialists) selected randomly by stratified random sampling from different clinical institutions, 105 of them were returned complete., Results: In all, 105 out of 115 (91%) questionnaires were returned complete. All of the candidates are male. For low-risk NMIBC follow-up, 46 of the specialists (79%) and 35 of the trainees (74%) decided to do a follow-up cystoscopy at 3 months after diagnosis, followed by a check cystoscopy 9 months later than yearly, while for high-risk patients, all of the specialists and 45 of the trainees (96%) decide to do a check cystoscopy every 3 months in the first 2 years after diagnosis. For upper tract follow-up in high-risk NMIBC, all of the urologists in the survey (specialists and trainees) routinely perform upper tract imaging in the form of a computed tomography scan with contrast in the first year after diagnosis. On the other hand, in the follow-up of the upper urinary tract in low-risk NMIBC, 16 of the trainees (34%) and 19 of the specialists (33%) still perform a yearly scan., Conclusion: Because of the high recurrence rate for NMIBC, this raises the importance of adherence to guidelines in the follow-up for these patients and, at the same time to avoid overdoing unnecessary cystoscopies or upper tract scans., Competing Interests: On behalf of all the authors, the corresponding author declares no conflict of interest, including employment, consultancies, stock ownership, honoraria, paid expert testimony, patent applications/registrations, and grants or other funding.Sponsorships or competing interests that may be relevant to content are disclosed at the end of this article., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc.)

A cancer tumor model is an important tool for studying the behavior of various cancer tumors. Recently, many fuzzy time-fractional diffusion equations have been employed to describe cancer tumor models in fuzzy conditions. In this paper, an explicit finite difference method has been developed and applied to solve a fuzzy time-fractional cancer tumor model. The impact of using the fuzzy time-fractional derivative has been examined under the double parametric form of fuzzy numbers rather than using classical time derivatives in fuzzy cancer tumor models. In addition, the stability of the proposed model has been investigated by applying the Fourier method, where the net killing rate of the cancer cells is only time-dependent, and the time-fractional derivative is Caputo's derivative. Moreover, certain numerical experiments are discussed to examine the feasibility of the new approach and to check the related aspects. Over and above, certain needs in studying the fuzzy fractional cancer tumor model are detected to provide a better comprehensive understanding of the behavior of the tumor by utilizing several fuzzy cases on the initial conditions of the proposed model.

Objectives: The aim of this study was to first assess the knowledge and perception of first-year university students in Iraq about COVID-19 in general and SARS-CoV-2 latest variant of concern, and to evaluate the attitudes towards protection measures including vaccination., Study Design: A cross-sectional study was conducted among newly enrolled students at the American University of Iraq-Baghdad. Mann-Whitney U and Kruskal-Wallis tests were used to test an association between the outcomes measured on a 5-point Likert scale and the binary and the categorical independent variables, respectively. χ 2 test was used to test the association between nominal categorical variables, while Kendall's τ-b was used for ordinal variables., Participants: Students (n=432) were invited to fill out a survey specifically tailored to assess their knowledge, perception and attitude towards Omicron variant and COVID-19 vaccines acceptance. 363 students enrolled in various majors participated in this study., Results: Assessment of COVID-19 knowledge and perception revealed that students still lack reliable info and data about FDA-approved treatment options (70.5%), SARS-CoV-2 variants (96.5%) and approved vaccines. Students' attitude and practices towards recommended safety measures should be reassessed to better manage the pandemic. Adherence level was shown to be associated with the belief in its capacity to effectively manage the new variant. Interestingly, 85% of the students have received at least one dose of approved vaccine. A significant positive correlation was detected between the level of adherence to recommended precautions and the intention to take a third booster shot if proven effective., Conclusions: Students' reliable knowledge about COVID-19 pandemic including the various strains and approved vaccines should be improved to better manage the pandemic and set foundations for a more appropriate approach when another pandemic occurs. Special workshops should be organised to ensure that students and the public have a more trusted source of information about COVID-19., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Older Syrian refugees in Lebanon are a marginalized population with under-recognized health needs. The inclusivity of this population within the humanitarian response is poorly understood. This study aims to identify the unique needs of older Syrian refugees in the context of recent concurrent crises in Lebanon, and explore the extent to which they are being met and prioritized by local and international aid agencies., Methods: We conducted in-depth interviews with a snowball sample of 26 stakeholders from 11 organizations operating in the health, nutrition, and water, sanitation, and hygiene sectors. Data analysis followed principles of thematic analysis., Results: Concurrent political, economic, and public health crises in host country promoted income insecurity among older refugees and increased dependency on younger relatives, leading to food insecurity, neglect, and poor health outcomes, including the sequelae of untreated non-communicable diseases. Mental illness was perceived to be exacerbated by Covid-19 related challenges, including social isolation, uncertainty about the future, and additionally due to feelings of guilt related to economic dependence and fundamental exclusion from labor force participation. Despite their vulnerability, older refugees are overlooked by the humanitarian response, which may be related to a lack of data. Pervasive medication shortages in the setting of the economic collapse, as well as inaccessible physical environments and competing interests were all identified as major barriers to care., Conclusions: Older Syrian refugees in Lebanon experience dual vulnerability that is acutely exacerbated in the setting of concurrent crises. Sociopolitical, economic, and cultural barriers promote social exclusion and may confer an increased risk of income and food insecurity in this population, with significant implications for health. Humanitarian aid agencies operating in the context of fragmented, under-resourced health systems are currently unable to sufficiently address multi-faceted needs of this community. We recommend moving away from a donor-dependent model of aid by allocating resources toward strengthening inclusive national health systems that emphasize preventative care. We further call for age-disaggregation of routine data and normalization of data sharing among stakeholders in the academic and public health sectors in order to develop evidence-based initiatives that can meet the needs of this under-served community., (© 2022. The Author(s).)

Fuzzy differential equations provide a crucial tool for modeling numerous phenomena and uncertainties that potentially arise in various applications across physics, applied sciences and engineering. Reliable and effective analytical methods are necessary to obtain the required solutions, as it is very difficult to obtain accurate solutions for certain fuzzy differential equations. In this paper, certain fuzzy approximate solutions are constructed and analyzed by means of a residual power series (RPS) technique involving some class of fuzzy fractional differential equations. The considered methodology for finding the fuzzy solutions relies on converting the target equations into two fractional crisp systems in terms of ρ-cut representations. The residual power series therefore gives solutions for the converted systems by combining fractional residual functions and fractional Taylor expansions to obtain values of the coefficients of the fractional power series. To validate the efficiency and the applicability of our proposed approach we derive solutions of the fuzzy fractional initial value problem by testing two attractive applications. The compatibility of the behavior of the solutions is determined via some graphical and numerical analysis of the proposed results. Moreover, the comparative results point out that the proposed method is more accurate compared to the other existing methods. Finally, the results attained in this article emphasize that the residual power series technique is easy, efficient, and fast for predicting solutions of the uncertain models arising in real physical phenomena.